Boosting natural capital

Boosting natural capital

Magazine R99 Features Boosting natural capital Researchers looking at the trends in global agricultural production as demand grows are urgently cons...

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Magazine R99


Boosting natural capital Researchers looking at the trends in global agricultural production as demand grows are urgently considering ways of developing sustainable production principles. Nigel Williams reports. Two of the first volumes this year of the Proceedings B of the Royal Society have been dedicated to the issue of sustainable agriculture, signalling researchers’ concerns about the urgent need to address this issue. The editors, Chris Pollock, Jules Pretty, Ian Crute, Chris Leaver and Howard Dalton, highlight issues that continue to fail to impact more widely. And they are blunt in their assessment of the upcoming challenges. There has been an extraordinary boom in agricultural production over recent decades but this is likely to be unsustainable. And the recent soaring prices for basic food commodities in the face of poor

harvests and rising global demand add weight to the issues raised. Pressure on land, both nationally and globally, will increase for at least the next half century, they write. Despite rapid shifts in human fertility patterns, population growth will result in the world population rising by at least another two billion to a maximum of 8.5–9 billion by 2045–2050. But there is no smoothness to these projected changes. “Projections of climate change impacts suggest that there will be significant negative impacts on crop and animal production, particularly in the subtropics and

tropics. At the same time, demand for animal products in developing countries is growing so fast that an extra 300 million tonnes of grain will be needed by 2050 to meet this need alone.” And water resources are under increasing pressure and shifting availability. Urban and industrial water use is reducing water availability for agriculture in many regions, and harvesting solar energy for biofuels and industrial feedstocks will further reduce land available for food production. “In our view, this means that agriculture in the twenty-first century will have to be very different from agriculture in the twentieth century and this, in turn, will require a radical approach to the investment in and application of research.”

Boom times: The increasing output of Chinese agriculture has matched industrial development but there is growing concern about how ­systems here and elsewhere can become sustainable in the longer term. (Photo: Copyright Lou Linwel/Alamy.)

Current Biology Vol 18 No 3 R100

Unless we look anew at agriculture in terms of the balances between wider benefits and impacts and link this to current and future societal drivers, we will continue to pay lip service to the concept of sustainability without ever developing ways to achieve it, they argue. Part of the problem in facing the future is the remarkable past achievements. In recent decades there has been a huge growth in agricultural production, with increases in food supplies across many regions of the world since the beginning of the 1960s. In one of the papers, Jules Pretty, at the University of Essex, writes that, since then, aggregate world food production has grown 145 per cent. In Africa it rose by 140 per cent, in Latin America by almost 200 per cent and in Asia by 280 per cent. The greatest increases have been in China, where a five-fold increase occurred, mostly during the 1980s and 1990s. In industrialized countries, production started from a higher base; yet still doubled in the US over 40 years and grew by 68 per cent in Western Europe. Over the same period, world population has grown from three billion to more than six billion, imposing an increasing impact of the human footprint on the Earth as consumption patterns change. Although per capita agricultural production has outpaced population growth for each person today, there is an additional 25 per cent more food compared with 1960. But these figures also mask regional differences. While Africa has increased production overall, per capita figures reveal that the continent is producing 10 per cent less today compared with 1960. Concern about sustainability in agricultural systems centre on the need to develop technologies and practices that do not have adverse effects on environmental goods and services, are accessible to and effective for farmers, and lead to improvements in food productivity, in contrast to many recent agricultural developments. Many researchers now believe that urgent new approaches are needed that will integrate biological and ecological processes into food production, minimize the use of those non-renewable inputs that cause harm

to the environment or to the health of farmers and consumers. There is also concern to make productive use of the knowledge and skills of farmers, to substitute human capital for costly external inputs, and make productive use of people’s capacities to work together to solve common agricultural and natural resource problems, such as for pest, watershed, irrigation, forest and credit management. One of the new concepts is improving ‘natural capital’ as a means of profiting from the best use of the genotypes of crops and animals and the ecological conditions under which they are grown or raised. Most agricultural sustainability improvements occurring in the 1990s and early 2000s appear to

have arisen despite existing national and international policies, rather than because of them, writes Pretty. Although almost every country would now say it supports the idea of agricultural sustainability, the evidence points towards only patchy reforms. Only three countries have given explicit support for sustainable agriculture: Cuba has a national policy for alternative agriculture; Switzerland has three tiers of support to encourage environmental services from agriculture and rural development; and Bhutan has a national environmental policy coordinated across all sectors. The authors hope that the new collection of reviews will help move this agricultural debate forward more widely.

New inputs

form allowed to thrive. However, wine- producers and scientists are now beginning to appreciate that more biodiversity could help to keep pests at bay and improve the yields and quality of crops. A research project sponsored by the environment charity Earthwatch is set to investigate the biodiversity in a traditional Bordeaux vineyard, Château les Vergnes, and to find ways in which the wine growers can work with nature rather than against

A new project looks at ways to boost natural methods to help manage some of the most valuable agricultural land in the world. Michael Gross reports. Travelling through wine-producing areas, one can easily get the impression that there is nothing but vineyards for miles around, and grapevines are the only life

Between the lines: Improving biodiversity amongst the rows of French vines may boost natural pest control amongst some of the world’s most valuable grapes. (Picture: Photolibrary.)